The second one is free. G33k on.
Serotonin [5-hydroxytryptamine (5-HT)]-mediated cardiac valvular disease has been commonly observed in patients with carcinoid tumors. Previous research by others using reverse transcriptase-polymerase chain reaction demonstrated that ...
www.ncbi.nlm.nih.gov
Xu J, Jian B, Chu R, Lu Z, Li Q, Dunlop J, Rosenzweig-Lipson S, McGonigle P, Levy RJ, Liang B (December 2002). "Serotonin mechanisms in heart valve disease II: the 5-HT2 receptor and its signaling pathway in aortic valve interstitial cells". Am. J. Pathol. 161 (6): 2209–18. PMID 12466135. PMC 1850896.
Don't know much about the 5-HTP effects but I wouldn't conlucude such thing (danger when occasionally ingesting) after quickly skimming through the summary of the first study. The second one is too much fo' me.